How to Read EIA's Weekly Natural Gas Storage Report — Net Change, Implied Flow, Five-Year Average and Margins of Error

As of 26 October 2026 (KST); most recently published weekly report: EIA's Weekly Natural Gas Storage Report for the week ending October 16, 2026, released October 22, 2026 at 10:30 a.m. eastern time; the next release is October 29, 2026. The schedule page says: "The standard release time and day of the week will be at 10:30 a.m. eastern time on Thursdays with the following exceptions." Primary source: https://ir.eia.gov/ngs/ngs.html^[1][5]

Comparison basis: all figures are EIA estimates of working gas, in billion cubic feet (Bcf). Stocks are measured as of the Friday of the report week ("Respondents provide estimates for working gas in storage as of 9:00 a.m. Friday each week."). The net change, the year-ago and five-year-average stocks and the percentage changes are published by EIA; the regional differences in Bcf are this page's subtraction of published rounded values. The table carries the note "Totals may not equal sum of components because of independent rounding." The report, its CSV file, notes, methodology, schedule and revision policy are all from EIA and count as one source.^[1][4]

In three lines

1. EIA's weekly report estimates how much working natural gas is held in underground storage in the Lower 48 states and five regions.
2. As published on October 22, 2026, stocks were an estimated 3,644 Bcf on October 16, up 77 Bcf on the week, 152 Bcf below a year earlier and 35 Bcf above the five-year average.
3. The next report is due October 29, 2026.^[1]

"Working gas in storage was 3,644 Bcf as of Friday, October 16, 2026, according to EIA estimates." "This represents a net increase of 77 Bcf from the previous week." "Stocks were 152 Bcf less than last year at this time and 35 Bcf above the five-year average of 3,609 Bcf." "At 3,644 Bcf, total working gas is within the five-year historical range."^[1]

Net change vs implied flow. "The weekly stocks generally are the volumes of working gas as of the report date." According to EIA's notes, the net change covers all events affecting working gas, including injections, withdrawals and reclassifications between base and working gas, while implied flow leaves out reportable reclassifications of 4 Bcf or more and may still contain unpublished net revisions of less than 4 Bcf. This week both columns show 77 Bcf for the total.^[3]

How the estimate is built. "This process ultimately results in about 80 to 85 respondents to the EIA-912 survey that are used for estimation, typically accounting for at least 90% of all storage volumes in a given stratum."^[4]

Regions vs the total. The five regions add up exactly to the 3,644 Bcf total this week (900 + 1,065 + 257 + 297 + 1,125), but South Central's salt (251) and nonsalt (875) facilities add up to 1,126 against 1,125 for the region (this page's calculation). The reason is in the methodology: "EIA performs independent rounding for all published weekly estimates of working gas stocks."^[1][4]

Standard error vs margin of error. The report publishes a standard error of 0.8 Bcf for the Lower 48 net change and a coefficient of variation of 0.4% for Lower 48 stocks. EIA defines the margin of error this way: "To determine the half-width of the confidence interval for a given published estimate, we compute the margin of error (MOE) defined as the estimated standard error of the estimate multiplied by the standard normal percentile for the level of confidence, rounded up to the nearest unit used in publishing the corresponding estimate." "For the standard normal percentile, we use 1.645 for a 90% confidence interval, and we use 1.96 for a 95% confidence interval." Applying that method, 1.645 x 0.8 is 1.316, rounded up to 2 Bcf, so the 90% interval for the 77 Bcf net change is 75 to 79 Bcf; for stocks, 3,644 x 0.004 = 14.576 Bcf (unrounded), and 14.576 x 1.645 = 23.98, rounded up to 24 Bcf, or 3,620 to 3,668 Bcf (this page's calculations; the published 0.4% coefficient of variation is itself a rounded value, so the true margin could differ slightly).^[1][4]

Coefficient of variation. "The coefficient of variation, which may also be referred to as the relative standard error (RSE), is the standard error expressed as a fraction of the estimate and is displayed as a percentage." "Note that for both the standard error and the coefficient of variation, the value for an aggregate level may not be computed by summing the corresponding values for its individual components." "As a result, estimated measures of sampling variability for estimates in the Pacific region will equal zero."^[4]

Year-ago vs last year's report. "The year-ago values in the weekly report are those estimates for the same day of the prior year as the current release." "As such, they do not match published data for the prior year." The year-ago total of 3,796 Bcf is therefore an estimate for October 16, 2025, the same calendar day.^[1][4]

Small changes and significance. "Computing a confidence interval in whole numbers centered about an estimate of weekly net change that is small in magnitude could lead to an incorrect conclusion that the estimate is not significantly different from zero." EIA's own example: "The MOE for a 90% confidence interval would be 1.645 x 2.2 Bcf, or approximately 4 Bcf, and the 90% confidence interval would be -50 +/- 4 Bcf, or -54 to -46 Bcf."^[4]

"Revisions are disseminated in the Weekly Natural Gas Storage Report (WNGSR) according to the established schedule and shall occur when the net reported changes to working gas levels are at least 4 billion cubic feet (Bcf) at either a regional level or for the Lower 48 states." "Reported revisions that reach or exceed 10 Bcf for the current or prior week at the regional level or for the Lower 48 states, and that are not the result of errors that accumulated in prior weekly periods, will be published in an out-of-cycle release of the WNGSR as described below."^[6]

The schedule lists holiday exceptions, including a Friday, November 13, 2026 release at 10:30 a.m. (Veterans Day) and a Wednesday, November 25, 2026 release at 12:00 p.m. (Thanksgiving Day).^[5]